This invention relates to a magnetic recording control apparatus for managing and controlling data of a large capacity magnetic recording medium.
Hereinafter, the description will be given referring to magnetic tape as an example of the magnetic recording medium.
In recent magnetic tape sub-systems, a multi-file system is known for recording a plurality of files on one tape to reduce the number of physical media that need to be stored.
JP-A-57-158008 discloses a system for allotting an address to each block on a magnetic tape medium and for making high speed location at the time of recovery of failure.
In recent magnetic tape sub-systems, a bulk write system, which includes an IC memory as a data buffer, stores data in the data buffer and then writes the data on the tape, and a pre-read or pushup read processing system which reads in advance data on the tape to a data buffer are known. The capacity of one magnetic tape has thus been increased due to the improvement in recording density and compression and interconnection of data blocks. Accordingly, although the data capacity (hereinafter referred to as the "capacity") of magnetic tapes that have been used practically (hereinafter referred to as the "conventional magnetic tape" or the "ordinary magnetic tape") has been at most about 200 megabytes, a magnetic tape cartridge having a memory capacity more than ten times as much as that of the conventional magnetic tapes (hereinafter referred to as the "large capacity magnetic tape") has been developed using this "data buffer" technique.
On the other hand, JP-A-57-152028 discloses a data control system by the division of a data buffer.